Turbine oil antioxidants



Dec. 14, 1954 R. v. wHlTE ETAL TURBINE OIL ANTIOXIDANTS Filed Feb. '7, 1952 om o@ um. o. Q, QN Q United States 2,697,07 Patented Dec. 14, 1954 ice TURBINE OIL ANTIOXIDANTS Ralph V. White, Pitman, and Henry D. Norris, Woodbury, N. J., assignors to Socony-Vacuurn Oil Company, Incorporated, a corporation of New York Application February 7, 1952, Serial No. 270,301

11 Claims. (Cl. 252-50) This invention relates broadly to mineral lubricating oils. It is more specifically concerned with mineral lubricating oils having improved resistance to oxidation.

As is well known to those skilled in the art, most lubricating oils are subject to oxidation during use. ln the case of highly-rened oils, such as are used to lubricate steam turbines, attack by atmospheric oxygen at elevated temperatures is most pronounced. Such attack occurs especially readily in the presence of catalytic metals, such as iron, copper, and copper alloys, which are encountered in steam turbines. The deleterious results of such oxidation are manifested by the formation of acidic substances, colored oxidation products, and sludge. It will be obvious to those skilled in the art that such conditions cannot be tolerated in such a finely-machined apparatus as a steam turbine.

It has now been found that the oxidation tendencies of mineral lubricating oils can be sharply inhibited by the addition thereto of a novel antioxidant. It has now been discovered that the reaction products of a tetrakis- (halomethyl)methane with certain aromatic amines, when added to mineral lubricating oils increases the resistance thereof to oxidation.

Accordingly, it is a broad object of the present invention to provide improved antioxidants. Another object is to provide mineral lubricating oils, such as steam turbine oils, containing effective antioxidants. A suecilc object is to provide reaction products of a tretrakis- (halomethyDmethane with certain aromatic amines. A further specific object is to provide mineral lubricating oils whose tendency to oxidize has been sharply reduced by the addition of small amounts of these reaction products. Other objects and advantages of the present invention will become apparent to those skilled in the art, from the following detailed description.

In general, the present invention provides a mineral y lubricating oil containing a small amount, sufficient to inhibit the oxidation tendencies thereof, of the reaction product obtained by reacting a tetrakis(halomethyl) methane with an aromatic primary or secondary amine;

using a molar proportion of aromatic amine to tetrakis- (halomethyl)methane of between about 2:1 and about 4:1, respectively, in the case of primary aromatic amines, and of about 4:1 in the case of secondary aromatic amines; and at a temperature of between about 180 C. and about 240 C.

The tetrakis(halomethyl)methane reactant employed to make the reaction products of this invention have th structural formula:

wherein X is a bromine, chlorine or iodine atom. Therefore, the reactants of this type which can be employed herein are tetrakis(bromomethyl)methane, tetraks- (chloromethyDmethane, and tetrakis(iodomethyl)methane.

The aromatic amine reactants utilizable herein are the primary aromatic amines and ring-alkylated derivatives thereof, and N-alkyl aromatic aminesv and ring-alkylated derivatives thereof. The aromatic ring nucleus can be any aromatic hydrocarbon ring. However, the benzene ring is preferred. The amine reactants contemplated herein are those having the general structural formula:

HRNY R', wherein R is a hydrogen atom or an alkyl radical having between one and 5 carbon atoms, R is a hydrogen atom or a primary or secondary alkyl radical having between one and 5 carbon atoms, and Y is an aromatic hydrocarbon ring, preferably a benzene ring. It has been found that amine reactants having tertiary alkyl substituents on the ring do not form reaction products which are effective in the present invention. There must be at least one hydrogen atom on the carbon atom of the alkyl radical which atom is attached to the aromatic nucleus. Non-limiting examples of the aromatic amine reactant are aniline, l-naphthylamine, p-toluidine, l-anthrylamine, o-toluidine, p-ethylaniline, o-isopropylaniline, p-sec-butylaniline, o-amylaniline, N-ethylaniline, N-tbutylaniline, N-isoamylaniline, N-methyl-o-butylanlline, N-propyl-m-toluidine, N-ethyl-p-toluidine, N-tamyl-p-isopropylaniline, N-ethyl-Z-naphthylamine, N- propyl-4-methyl-l-naphthylamine, N-buty1-6-sec-amyl-2- naphthylamine, 6-methyl-2-naphthylamine, 4-butyl-1- naphthylamine, S-methyl-Z-anthrylamine, 4-propyl-1-anthrylamine, N-isopropyl-S-sec-butyl-1-anthrylamine, N- methyl-ll-amyl-9-anthrylamine, 9-phenanthrylamine, and 4-butyl-1-phenanthrylamine.

'l'he molar proportions of tetrakis(halornethyl)methane reactant and amine reactant used to produce the reaction products of this invention depend upon Whether the amine reactant is a primary or a secondary amine. A primary aromatic amine can be reacted in a molar proportion of amine reactant to tetrakis(halomethyl)methane reactant of between about 2:1, respectively, and about 4:1, respectively. in the case of a secondary aromatic amine, however, there must be a molar proportion of amine reactant to tetrakis(halomethyl)methane reactant of about 4:1, respectively. ln general, there must be at least enough equivalents of hydrogen supplied by the amine to react with all of the halogen equivalents of the halogen compound reactant.

The temperature of the reaction is a critical factor. In general, satisfactory reaction products are produced at temperatures varying between about C. and about 240 C. lt is preferred, however, to operate in a ternperature range of from about 215 C. to about 230 C. Reaction products produced at temperatures higher than about 240 C. are ineffective for the purposes of this inventlon.

'lhe time of the reaction is not a critical factor. It will vary dependent upon the particular reactants involved and upon the reaction temperatures selected. The reaction is carried out until all of the halogen atoms in the tetrakis(halomethyl)methane reactant have combined with hydrogen atoms. ln general, the reaction is complete in between about 3 hours and about 15 hours.

In order to ensure complete reaction, the hydrogen halides formed as by-products in the reaction of this invention should be removed by means of a hydrogen halide acceptor. Such an acceptor can be an inorganic base or a tertiary amine. Since the amine reactant used in the present reaction can itself combine with, i. e., accept, a hydrogen halide, the acceptor must be a stronger base than the amine reactant. As those skilled in the art will recognize, the relative strength of basic materials can be readiiy determined on the basis of ionization constant data. ln any given pair, the base having the higher ionization constant (K) is the more basic. For example, for aniline the Value of K is 3.83X1010, Whereas tributylamine has an ionization constant of 1x10-4. Since the tributylamine has the higher ionization constant, it follows that it can be used as an acceptor in a reaction involving aniline. This has proven to be the fact, in actual practice. The ionization constants can be readily determined by well known methods. Many values are available in tables, for example in Langes Handbook of Chemistry and from sources set forth therein. Non-limiting examples of hydrogen halide acceptors utilizable herein are triethylamine, ethyldipropylamine, triisopropylamine, amyldipropylamine, tributylamine, triisobutylamine, dimethylbenzylamine, triamylamine, trioctylamine, pyridine, piperidine, caffeine, tetramethylethylenediamine, sodium carbonate, sodium bicarbonate, and sodium acetate. At least sutlicient acceptor to react with all of the hydrogen halide produced 3 in the reaction must be used, i. e., at least 4 moles of hydrogen halide acceptor per mole oftetrakis(halomethyl) methane. ln practice, it is preferable to use a molar excess of hydrogen halide acceptor. Generally, between about 4.1 moles Aand about 5 moles of acceptor will be...

used per mole of ,tetrakis(halomethyl,)methane,.` As will be readily understood by those skilledrin .the art, in some..

instances an excess ofthe amine reactant can lbe usedas, a hydrogen halide acceptor, Whenfour moles of aprimary or secondary amine are reactedper mole. of rtetrakis- (halomethyDniethane reactant, Vthe reactant amine can. be used as an acceptor, Thus, aI molar. proportion, of8:1

or higher can beemployed; four -moles of .amine foixthe. i reaction product production, andthel other.four .moles as the hydrogen halide acceptor. Y,

The reaction of ,this invention Canbecarried outieitlierl in an open reactorhorinv a closed reactor.4 ferred, however, 4to conduct thereaction. ina sealedreactor, in order to exclude atmospheric moisture.y .It hasv been found that thepresence of smallarnounts vof.water, in the reaction system makes it diicult to attain .the

temperatures required. Vfor ,the,reactitzgne The constitution ,of` thet reactionpr'oductslofl this,.iii. vention is not known. V,It couldbepostulatednin lview of the usual mechanisms .of condensation `reactions v bez It is pretween amines and alkyl halides, that'the aminereactant simply replaces the halogen atomsV of .the=tetrakis(halo. v

methy1)methane reactant. This does notf appear to be thecase, however.

The reactioriproductsy of the pres-., ent invention have molecular weights` which4 are. higherv On the other hand, the molecular weights` are..v

invention, other than a definition comprising the method f or making them, is highly. inaccurateand-non-descripf reaction products contemplatedherein., In the interests of brevity, molar proportions` are indicated by inserting.

the number of moles of va reactant usedin parentheses Thus, -aniline(2,) |tetrakis(bromo. i methyl)methane(1) indicates thel reaction productvbe-.

following its name.

tween aniline and tetrakis(bromo`met hyl)methane .in a

molar proportion of 2:1, respectively. Non-limiting ex-l amples of pairs of reactants are; aniline@)4-tetrakis-A (chloromethyl)methane( l) ,1-naphthylamine(.4), -i-tetrakis (bromomethyl methane I1, p-toluidine 2,) -I-tetrakis- (chloromethyl) methane( l 4V butyl 1 phenanthrylw amine(3) -i-tetrakisodomethyl)methane( 1) 9-phenan--y (bromomethyl)methane( 1 o f, toluidine( 3) -,|tetrakis'- i (chloromethyl) methane( 1 1 Y, anthrylamine 2) -{-tetra.Y

kis(,iodoniethyl)methane(l);A p ethylaniline(4) -t-tet-A ide.

pylaniline (4) +tetrakis iodomethyl) methane 1 ),K; p secbutylaniline (2) -i-tetrakis (bromomethyl) methane( 1) loamylaniline 3 ,-ttetrakis chlorornethyl) methane( l butyl 1 naphthylamine(4)-I-tetrakis(iodornethylhneth- 2 naphthylamine(4)-i-tetrakis(bromomethyl)methane t... (1); N ethylaniline(4)-iftetrakis(chloromethyl)methane(1); yN t butylaniline(4)+tetrakis(iodomethyl)- methane( 1 methyl)methane(1) N propyl 4 methyl l naphthylamine(4) +tetrakis(bromomethyl) methane( 1 methyl o butylaniline(4) -i-tetrakis (chloromethyD- kis(iodomethyl)methane(.1); Nft amyl p isopropylaniline 4) -i-tetrakis bromomethyl methane( l.) N-ethyl p to1uidine(4) {tetrakis( chloromethyl)methane (Il methane( 1).

tive. '10 i The following combinations will serve as, non-ligniting examples of the pairs of reactants which ,will form theA in the art. It is, of course, necessary to remove the hydrogenfhalideacceptor and the hydrogenhalide'z' 'Suit' ably, the hydrogen halide can be removed by extracting the reaction mixture with a strong solution of caustic, such as sodium or potassium hydroxide. In some instances, the amine hydrohalide formed from the addition of an amine acceptorwith-hydrogen halide can be removed by ltration. The reaction products of the present invention are relatively high-boiling. Accordingly, organic hydrogen halide acceptors can .be removed by distillationmethods. Steam distillation and distillation under reduced pressure are suitable methods. Afterlremoval of the acceptor, hydrogen halide, and the like, it is desirable, though not essential, to extract the;.residual reaction product with a water-insoluble solvent, in order to isolate the reaction product ."frominorganic salts and the like. Suitable solvents are diethyl ether, benzene, chloroform, toluene, xylene, etc. The extracts can be Vcombined and evaporated or-'distilled to removethe solvent, thus leaving the desired reaction product. As indicated hereinbefore,vhowever,`this.step is not necessary.

The residual reaction product 4remaining inY the tistilla` tion vessel is vutilizable assuch, provided the caustic maods, such as. by a washingoperation.

The following-specic.examples-arev-for the purpose of exemplifying and illustratingthe' present invention.

tions described therein. As -Will be vapparent to those skilled in the art, a Vwide variety of otheru reactants, as

terial, inorganic salts, etc., are removed by 'other'meth--1 set forth hereinbefore, can be used tofprepare theprod .ucts contemplated herein.

EXAMPLE 1y methane(1) in an open vessel A mixture'tof 19.4 grams.(0.05` mole)v of `tetrakis (bromomethyDmethane, 9.3 grams:(0.1.mole) of aniline,

and 46 grams (0.25) mole of tri-n-buty-laminewere and a reflux condenser.

period, the temperature ofthe reaction mixture rose from ov C. to 226 C. The reaction mixture ,was` cooled and then madestrongly. alkaline bythe addition of 400 milliliters of a 5 per cent (weight) aqueous -solutionof sodium. hydroxide.

organic material coming Lover with the steam-distillate. The residuefemaining inthe-flask was cooled and'extracted with about 200 milliliters of diethyl ether.

colored, oil-soluble .oily material... `It contained 7.48 per` cent nitrogen and hada molecularweightot` 406.1 The product gave :a negative` test. for-halogen.

EXAMPLE 12v i, .a

Reaction of aniline (2) with tetraks(brbinomethyl)- methane(1) in a closed reactor the mixture was subjected to steam'distillation until no y appreciable amount of organic matter distilled over. A

This mixture `was then subjected-to u steam. distillation until 7.5 liters of steamdistillatehad been collected. At this point,vthere was `substantiallyno The i ether solutionwas washed with Water to remove -iwater- 1-f soluble material, andl dried over solid potassium hydrox 1 The ether solution of ithe product was` ltered. Then the solvent (ether) was yremoved by evaporation on the steam bath. The product (10.5 grams)- was a.dark

total of 8.5 liters of steam distillate were collected. i The Separation of the reaction products :of this. inventioni,

is readily. effected by methodswell known-.to those skilled.

residue was kcooled and .taken up lin `about 300- milliliters of diethyl ether. The ether solutionwas washed with water and` then dried over solid potassium hydroxide.

product contained 7.21 per cent nitrogen, had a molecular Weight of 406, and contained no halogen.

EXAMPLES 3 THROUGH 7 Five reaction products were prepared, using the pro-v cedure described in Example 2, by reacting tetrakis- (bromomethyl)metharie with diterent aromatic amine reactants, in several molar proportions and at various Two base oils were used in evaluating the reaction products aforedescribed. Base oil A is a solvent refined Mid-Continent (Rodessa) distillate stock having a specific gravity ot' 0.860, a flash point of 405 F., and a viscosity of 155 S. U. S. at 100 F. Base oil B is an acid-refined Mid-Continent distillate stock having a specific gravity of 0.879, a flash point of 385 F., and a viscosity of 152 S. U. S. at 100 F. Both of these oils are suited for use in steam turbines.

EXAMPLE 8 The reaction products prepared as described in Examples 1 through 7 were subjected to the Brown-Boveri Turbine Oil Test. This test is described in the Brown- Boveri Rev., 16 (2), 92-7 (1929). In brief, a 200` milliliter sample of oil under test is placed in a 400-v milliliter covered beaker containing a V-shaped piece of polished copper. Air is passed over the surface of the oil at a rate of two liters per hour. The test is carried out for 72 hours at 230 C. and then for 24 hours at room temperature. The results, in terms of condition of the copper, neutralization number (N. N.), and Lovibond color, indicate the oxid-ation stability of the oil tested. These results are compared with similar results for the uninhibited base oil. Pertinent test results for the reaction products of Examples l through 7 are set forth in Table II.

in acidity, a sign of the formation of acidic oxidation products. These data are usually plotted graphically. Color can also be noted, ahhough acidity is the primary criterion in this test.

In addition to the uninhibited base oils A and B, four other blends were tested in this test. Blend R was a blend of 0.2 weight per cent of the reaction product of Example 1 in base oil A. Blend S was a blend of 0.2 per cent of the same reaction product in base oil B. Blend T was a blend of 0.2 weight per cerit of the reaction product of Example 3 in base oil A. Blend U consisted of 0.2 per cent, by weight, of the reaction product of Example 7 in base oil A. Pertinent data for these runs are set forth in Table III.

TABLE III [ASTM Turbine Oil Oxidation Test Results] Lovi- Blend Data Hours Days bond N. NJ

Color 24 1 3 0. 05 Base 011 A 48 2 14 0.92

72 3 172 5.1 120 5 7 0. 02 144 6 1.8 0.08 Base O11 B 168 7 5 0.55

194 8 16 1. 9 219 9 32 3. 2 1,920 2 0.04 2, 952 123 2. 5 0. 02 Blend R 4, 176 174 4 0.06 4, 848 202 8. 7 0.70 4, 944 206 78 5. 7 1, 584 66 13 0. 24 ist a 19 22 0. 65 Blend S 2, 016 s4 25 0. ss

2, 112 88 62 1. 4 2, 256k 94 285 14. 1 te t t i 0.04 Blend T 3, 552 148 9 o. 06 4, 512 188 12 0.06 1,848 77 6 0.06 2,352 98 6 0.04 Blend U 3, 552 148 6 0.06

l Neutralization number.

In the figure, the acidity (N. N.) data for the -i'uns reported in Table III are plotted graphically. As will be apparent from the curves for oils A and B, the uninhibited oils rapidly undergo oxidation. The curves therefor are typical; in that the acidity of the oil remains low until oxidation commences. At that point, acidity in- TABLE II [Brown-Boveri Turbine Oil Test.]

Results ln Base Oil A Results in Base Oil B Wt. Per- Additive Ccent LWL Lovi one bond N. N.1 Copper bond N. N.1 Copper Color Color 58 0.19 O.K s 0.07 O. K. 2.5 0.02 o. 2.5 0.03 0.1i. 9.0 0.0i 0. 12 0.07 o. K. 5.0 0.02 0.K. 9 0.02 0. K. 16.0 0.01 0.K 4o 0.47 0. K. 7.0 0.05 0. K. 12 0.05 o. K. 90.0 0.16 Bright 46 0.60 o. K. 1.3 0.03 .K 4 0.05 O. K.

1 Neutralization number.

EXAMPLE 9 creases rapidly, often within a matter of a few hours. Some of the reaction products described in the preced- It .will'be noted that test blend R (0.2 per cent Example ing examples were subjected to the ASTM Turbine Oil 1 1n oil A) maintained a low acidity for 200 days. It Oxidation Test. This test is fully described in the ASTM was not until over 200 days (not shown) that the rate Manual as Test D-943-47T. ln general, the test involves of oxidation had increased to the point that acidic bodies placing a 3D0-milliliter sample of test oil in a vtube prohad been formed to an appreciable extent. The blend vided with a gas inlet having a fritted glass outlet, and of acid refined base oil B containing 0.2 per cent of the a catalyst coil consisting of interwound iron and copper product of Example 1 lasted for almost 90 days, before wire. The test is conducted at a temperature of i203i its acidity increased tremendously. As is well known ().9 F. Sixty milliliters of Water are maintained in the to those familiar with the art, acid refined oils are much tube, and oxygen is passed through the oil at the rate more difficult to inhibit than are solvent refined oils. of three liters per hour. The test is continued until Accordingly, the difference in response of oils A and B period testing shows that the oil has greatly increased to the same additive is to be expected. Test blend T (0.2 percent 'of product of 'Example 3 tir: base oil fA) had an extremely low N.jN. even at V188 days andshowed no signs of becoming oxidized. The blend 'of 0.2 per cent of the product of Example 7 in -base oil B (Curve U) lasted for about 180 days before it -showed'appreciable acidity.

In the `foregoing examples, the preparation and the effectiveness of the reaction products of this invention have ybeen demonstrated. It will be appreciated'that these products are excellent stabilizers for lubricating oils. Also, it will be noted that theyare effective in stabilizing both solvent rened oils and acid rened oils against oxidation. A

The amount of the reaction products of this invention which is blended with a mineral lubricating oil varies between about 0.05 per centand rabout p'er cent, by weight. It is ordinarily preferred to use between about 0.1 per cent and about 2 per cent, by weight. Concentrates of these reaction products in mineral oils -are contemplated. ,Accordin'g1y, more than 5 per cent, and up to 49 Vper, cent of the reaction products (limited by .the dispersibility thereof in mineral oil) might be blended in a mineral oil, which oil need not be theesatne type of' oil that is ultimately used. Thus, a concentrate can be prepared in a light oil, such as a kerosene or light household oil. requisite amount, in the oil to be inhibited, in order to achieve a blend containing the desired amount of additive.

Other oil addition agents can be used-inV conjunction with the additives of this invention, to improve other propertiesof the oil. For example, antirust agents, oiliness agents, V. I. improvers,A pour point depressants, detergents, antifoamants, EAP. agents and thelike .can beadded to the lubricating oilalong with the additives of this invention. Such other additives are well known to those familiar with the..art. Accordingly, it is, believed unnecessaryto list them here.

Although the present invention has been described with preferred embodiments, it is to be understood that modications and variations may be resorted ,to` without. departing 'from the spiritand scope thereof, as those skilled in the art `will readily understand. Such variations andmodicationsare considered' to be within-the" purview and scope of the appendedA claims;

What is claimed is:V

l. A mineral lubricating oil containing, a small amount, sucient to inhibit the oxidation tendencies thereof, of the reaction product obtained by reacting 1). al tetrakis (halomethyl') methane of the general otmu'lat:

wherein X is selected from the group consisting of bromine, chlorine and iodine, with (2) an amine -.havingI the general formula HRNYR' wherein Y is a benzene nucleus, R is a radical selected from the group consisting of hydrogen and an alkyl radical having from one to` 54 carbon atoms, and R is a radical selected from the group consisting of hydrogen and an alkyl radical havingfroni;

one to 5 `carbon atoms and having at least one hydrogen 0.05 per cent and about 5 per cent, by weight, of thereaction product obtained by reacting (l)Y a tetrakis(halo-- methyl)methane of the general formula:

The concentrate can thenbedissolved,V inv the' wherein X is selected from the group consisting ofbio mine, chlorine and iodine, with (2) a'n amine having 'the general formula HRNYR wherein Y is a benzene nuc1eusR is a radical selected from the group consisting of hydrogen and an alkyl radical having from one to 5 carbon atorns and R is a radical selected from the group consisting of hydrogen and an alkyl radical having from on'e'to 5 carbon atoms and having at least one hydrogen atom attached to the carbon atom thereof which is attached to the aromatic nucleus, at a temperature of from about 180 C. to about 240 C.; the proportion of said amine Vto said tetrakis(halomethyl)methane utilized in the reaction being from about 2 to about 4 mols of said amine per mol of said tetrakis(halomethyl)methane whenftheV radical R in said amine is hydrogen and about 4 mol-sof said amine per mol of said tetrakis(halomethyly methane when the radical R in said amine is alkyl.

3. A mineral' lubricating oil containing a small amount, sufficient to inhibit-"the"mcidation'tendenciesV thereof, of

the reaction product obtained by reacting tetrakis(hromo-` methyl)methane with aniline, in a molar proportion of said anili'n'e to .said tetrakis(brmomethyD'rnethaiie of about 2:1,.'rjespectivelygand at a temperature of between about 180 C. and about 240 C.

4., A` mineral lubricating oil containing alsmall amount, sufficient to inhibit the oxidation tendencies thereof, of. the reaction product obtained by reacting a tetrakis- (bromometiiyumethane with aniline, in a molar proper'` tion of said aniliiie to said tetrakis(bromornethynmethane of about 4:1rv respectively; and at a temperature of between about 180 C. and about 240 C'.

5, A mineral lubricating oil containing a s'rnall amount, suiiicient to inhibit the oxidation tendencies thereof, of the reaction product obtained by reacting tetrakis(bror`n`o methyl)methane with p-toluidine, in a molar proportion of said p-toluidine to said tetrakis(hromomethyl)methane of about 22.1, respecfivel'y;4 and at a temperature of betwleen about 1805" C. and about 240 C.

- mineral lb'ritingzoil Containing a srnall amount,

- suiiet to inhibit the oxidation tendencies thereof,l of

the reaction Iproduct obtained by' reacting. a tetrakis- (brmornetbylmethane.with N-ethylaniline, in a molar proportion: of said N-etlylaniline to said tetrakis(bromo methyl)methane of about 4:1,V respectively; and at temperature of between about 180 C. and about 240 C. 7-. The reaction product obtained by reacting (l) a tetrakis(haloinetl'tyl)methane` of the general formula:

" wherein.` Xis' selected from the group consisting ofV brothine, chlorine and iodine, with `(2) an amine having the 'general formula HRN-YRJ wherein Y is a benzene nucleus, R is a radical selected from the group consisting of hydrogen van an alkyl radical having from one to 5 cai-bon atoms and R isa radical selected from the group consisting of hydrogen andfan alkyl radical having from one to 5 carbon atoms andi havinga-t least one hydrogen atom attached to the carbon atom thereof which is attaehed to the aromatic nucleus, Vat a temperature of froml about C. to about 2`40v C.; the proportionv of. saidanine to said tetrakis(halometliyl)methane utilized in the reaction/being. from about 2 to' aboutA 4 mols of said amineper mol of said tetrakis(halomethyl)methane when the radical R in said amine is hydrogen and about 4 mols of said amine per mol of said tetrakis(halomethyl) methane when the radical-R inV said amine is alkyl.

8. The reaction product obtained by reacting a tetrakis-l (bro'rno'ni'ethyl2)irietha'ne'y with aniline, in` a molar propor tionof said` aniline t'o said tetrakis(bromomethyl)' methane f about 2:-l, respectively; and at a temperatureofbetween'fabout 180 C. and about 240 9i. The reaction product obtained by reactinga tetrakis- (bromoniethylrnethane with' aniline, in a molar propor-v tion-.of said anili'ne to said tetrakis (bromomethyDmethaneof' about 4:11, respectively; andy at a temperature of be-4 tween about 180" Ci. a'nd about 240" C.

10. The rfeactiontpro'dtobtained'by reacting a tetrakis- (brornornothylljmethane with p-tluidine', in' amol'arproepome" snap-remitirse to`-1 said` tetrakiswrememesiyi)e References Cited in the le of this patent Number UNITED STATES PATENTS Name Date Watson Oct. 19, 1948 Hollis Nov. 21, 1950 

1. A MINERAL LUBRICATING OIL CONTAINING A SMALL AMOUNT SUFFICIENT TO INHIBIT THE OXIDATION TENDENCIES THEREOF, OF THE REACTION PRODUCT OBTAINED BY REACTING (1) A TETRAKIS(HALOMETHYL) METHANE OF THE GENERAL FORMULA:
 7. THE REACTION PRODUCT OBTAINED BY REACTING (1) A TETRAKIS(HALOMETHYL) METHANE OF THE GENERAL FORMULA: 